GEOG101 Exam #5

What is a biome?

A large geographic area defined by climate, vegetation, and animal life

What two major factors determine biome distribution?

Climate and terrain

What climatic factors influence biomes?

• Atmosphere & the circulation systems 

  • Moisture carrying air masses and their distribution

• Solar radiation 

  • Latitudinal variation in shortwave radiation

How does latitude affect climate?

It controls the amount of incoming shortwave solar radiation

What terrain factors influence biomes?

• Distribution of land masses and oceans

• topography of continents

Where are tropical rainforests located?

Near the equator

What climate defines tropical rainforests?

• Hot, humid, high rainfall

• dense, layered structure

Why do rainforest trees have shallow roots?

Nutrients are concentrated near the surface

What are buttress roots?

Wide roots that stabilize large rainforest trees

What defines a tropical savanna?

Warm temperatures with distinct wet and dry seasons

What vegetation dominates savannas?

Grasslands with scattered trees

What animals dominate savannas?

Large grazing herds and predators

What characterizes a thorn forest?

Drought-resistant, thorny trees and shrubs

What type of trees dominate thorn forests?

Deciduous trees

What defines a desert biome?

Extremely sparse vegetation due to low moisture

What are ephemeral desert plants?

Plants that complete their life cycle in one growing season

What are perennial desert plants?

Slow-growing, water-storing plants

What animals are common in deserts?

Rodents, insects, and reptiles

What defines temperate grasslands?

Dominance of grasses, moderate rainfall, hot summers, cold winters

Where are temperate grasslands typically found?

Large continental interiors

What animals dominate temperate grasslands?

Large grazing herds and predators like wolves.

What defines temperate forests?

Four seasons with deciduous and coniferous trees

What tree types are found in temperate forests?

Deciduous (oak) and coniferous (pine)

What defines a Mediterranean climate?

Hot, dry summers and cool, moist winters

Where are Mediterranean biomes located?

Coastal California, central Chile, SW Australia, Mediterranean Sea

What vegetation dominates Mediterranean biomes?

Waxy-leaf shrubs and widely spaced trees

What defines the northern coniferous forest?

Long cold winters and warm, humid summers

What is the northern coniferous forest called in North America?

Boreal forest

What is the northern coniferous forest called in Russia?

Taiga

What vegetation dominates this biome?

Dense coniferous trees

What defines the tundra?

Very cold winters and short growing seasons

What plants dominate the tundra?

Mosses, lichens, sedges, and small shrubs

How does tundra biomass compare to fauna?

Low plant biomass but relatively large animal populations

What is zoogeography?

The study of the geographic distribution of animal species

What defines a species?

Organisms that can produce fertile offspring

What did Alexander von Humboldt contribute?

Linked altitude, temperature, and vegetation

What did Charles Darwin contribute?

Theory of natural selection

What evidence did Darwin study?

Finch beak differences on islands

What did Alfred Russel Wallace identify?

Wallace’s Line separating marsupial and non-marsupial fauna

What is an animal’s range?

The geographic area where it is found

Besides climate, what affects animal range?

Vegetation

What is a habitat?

The physical environment an organism lives in

What is an ecological niche?

The environmental role where an organism functions best

What drives natural selection?

Reproductive success and genetic variation

How do mutations affect evolution?

Mutations continually add to genetic variation

What is gene flow?

The movement of genes between populations

How does high gene flow affect evolution?

It limits natural selection

How does low gene flow affect evolution?

It allows populations to diverge

What are zoogeographic realms?

Large regions with distinct animal populations due to isolation

What barriers create zoogeographic realms?

Mountains, deserts, oceans, and land bridges

What is convergent evolution?

Unrelated species evolve similar traits

What is divergent evolution?

Related species evolve differently due to isolation

Which realm has the most diverse fauna?

Paleotropic

What characterizes the Indomalayan realm?

Some shared fauna like elephants and lions

Why is Madagascar’s fauna unique?

Long-term isolation and low gene flow

What defines the Australian realm?

Marsupials due to prolonged isolation

What defines New Zealand’s fauna?

Many flightless birds

What defines the Neotropic realm?

Rich fauna like jaguars, tapirs, and boas

Which realms are least diverse?

Nearctic and Palearctic

What is the littoral zone?

Shallow nearshore area where sunlight reaches the bottom

What is the coast?

The broad region near the sea

What is the shore?

The land at the edge of water

What is the shoreline?

The line where water meets land

What is wave height?

Distance from crest to trough

What is wavelength?

Distance between wave crests

What are waves of oscillation?

Waves where energy moves but water stays in place

What causes ocean waves?

Friction from prevailing winds

What is shoaling?

Increased wave height and decreased wavelength near shore

What are breakers?

Waves that collapse as they reach shallow water

What is surf?

sequence of breaking waves

What is swash?

Water rushing up the beach after a wave breaks

What is a rip current?

narrow current flowing away from shore

What is wave refraction?

Bending of waves due to changing water depth

What is longshore drift?

Sediment movement parallel to the shoreline

What causes tides?

The moon’s gravitational pull

What are tidal forces?

Differences in gravitational pull across Earth

What is the nearshore zone?

Always submerged area with longshore bars

What is the foreshore?

Area submerged at high tide and exposed at low tide

What is the backshore?

Area above high tide containing dunes and berms

What is a berm?

A bench formed by wave action

What are beach dunes?

Wind-formed hills or ridges of sand

What is a sandspit?

narrow projection of sand into water

What is a sandbar?

A long, narrow offshore sandbank

What can sandbars develop into?

Barrier islands

What is a baymouth bar?

sandbar that closes off a bay

What is an estuary?

tidal river mouth where freshwater meets seawater

What is a lagoon?

shallow body of water separated by a natural barrier